BOISE, Idaho (AP) -- The river-bend outpost that is Riggins, Idaho, has been obscured for weeks with the charred remains of evergreens wafting down and littering parked vehicles with ashes in the shape of pine needles that crumble to the touch.

The town of 419 is surrounded by mountains, but some days they're shrouded by a smoky haze hovering in the air from wildfires still scorching the area.

"You can smell it," said Riggins Mayor Robert Crump on Friday. "There's still stuff falling."

Wildfires in the state are less active as cooler fall weather sets in at night and the daytime humidity rises. But, without help from rain or snow, Idaho's worst wildfire season since 2007 appears set to keep smoking.

And, according to federal meteorologists, no such help is in the forecast.

That means towns such as Riggins can probably expect the bad air to linger for weeks -- or longer.

Shelby Law, U.S. Bureau of Land Management meteorologist who helps predict fire danger for Idaho, said some interesting benchmarks underscore why the 2012 fire season will be remembered as long, severe and very expensive.

For instance, the fire season in 2007, when an area three times the size of Rhode Island burned, ended when a big rain and snow storm hit the first week of September. This year, October has arrived, with no such weather in sight.

Hundreds of firefighters are still busy on the 23-square-mile Wesley Fire upstream of Riggins, a big wildfire that got started late in the season.

"It's not very often we have new team fires in September," Law said, adding the El Nino weather pattern predicted for this winter could set the region up for another bad fire season in 2013. "If it does happen, we'll be right back in it next year. Wildfire potential will remain in elevated in the West."

So far, the costs for all Idaho's suppression efforts aren't in, but early estimates show a heavy expense.

Fighting the Wesley Fire, sparked by lightning along U.S. Highway 95 on Sept. 9, has cost $11.5 million so far.

That's nothing compared to the Mustang Complex, a fiery collection of nine blazes near the Idaho-Montana border that have cost more than $35 million after starting July 30, again by lightning.

In just the southern portion of the state, large fires have cost $143 million for the federal government to fight this year, so far, according to the Eastern Great Basin Coordination Center.

And that doesn't include blazes in Idaho's northern half still gobbling up resources. For instance, costs of fighting the Sheep Fire, another rare September start north of Riggins along Highway 95, already exceed $12 million and counting.

"We're hoping as the days get shorter, and we get some more humid days, that it will eventually burn itself out," said Dan Bastion, a fire spokesman there. "We're standing back and letting it do what it's doing, because it's not very active."

Idaho's state firefighting costs are running about $23 million, though some $8.5 million will be reimbursed by the federal government, said Department of Lands spokeswoman Emily Anderson.

The average for the last five years is just $8.6 million, Anderson said.

State Department of Environmental Quality officials expect Idaho's normally brilliant fall to be largely cloaked in smoke, some places more than others.

In southwestern Idaho, where Boise and the state's largest population center are located, air quality Friday was "yellow," meaning conditions won't create health problems for most people, but the region typically has clear skies, with air quality in the "green" zone, with little or no risk from pollution.

"Until we get that one season ending event, one that clears us out, we'll have that haze and smoke," said Michael Toole, DEQ's regional air-shed quality coordinator.

But everything is relative, as even a "yellow" air quality rating would be welcome in Salmon or Riggins -- towns near the fire lines where unhealthy air will persist for the foreseeable future, according to DEQ forecasts.

"Our population is a lot of seniors," said Crump, Riggins' mayor. "I know there are several folks in town that are having issues with this. They're ready to see it end, immediately."